Atmospheric pressure chemical vapor deposition of WSe₂thin films on glass—highly hydrophobic sticky surfaces

Abstract

Atmospheric pressure chemical vapour deposition (APCVD) of tungsten selenide films on glass substrates was achieved by reaction of diethyl selenide with WCl 6 at 500-650 uC. X-Ray diffraction showed that the WSe 2 films were crystalline with cell constants close to those expected-some preferred orientation was noted at higher deposition temperature. Energy-dispersive analysis by X-rays (EDAX) gave a W : Se ratio close to 1 : 2 for all the films formed at 550 uC. The films were matt black in appearance, were adhesive, passed the Scotch tape test but could be scratched with a steel scalpel. SEM showed that the films were composed of either plate or needle like crystals which become longer and thicker with increasing deposition temperature. The films were highly hydrophobic with contact angles for water droplets in the range of 135-145u. Furthermore these surfaces were highly adherent for water droplets-that did not roll or slide even at a tilt angle of 90u.

Tribological properties of WSe2 nanorods as additives

“…The Raman pattern (Fig. 2) is further demonstrated the nature of WSe 2 nanorods, the main peak around 249 cm -1 , showed the similar data [15]. Figure 3a reveals the general morphology of the WSe 2 nanorods.…”

“…For example, nanoparticles of WSe 2 were synthesized by a chemical reaction between W(CO) 6 and Se in a closed reactor [9]. And the thin films of WSe 2 were obtained by many processes, such as a solid-state reaction, chemical vapor deposition, electrodeposition, rfsputtering [10][11][12]. Nanotubes of WSe 2 were synthesized [13] by the reduction of the corresponding triselenides in hydrogen or by the decomposition of the ammonium selenometalates in a hydrogen atmosphere.…”

Constructing monodispersed MoSe2 anchored on graphene: a superior nanomaterial for sodium storage

“…Double peaks at 55.0 and 54.1 eV (Fig. 3e) attributable to the core levels of Se 3d3/2 and Se 3d5/2, respectively, are the characteristic of Se 2− in MoSe2/rGO hybrid nanostructures [29,30]. From Fig.…”

Accessing new 2D semiconductors with optical band gap: synthesis of iron-intercalated titanium diselenide thin films via LPCVD

“…Chemical vapour deposition (CVD) has drawn attention as a method to synthesis thin lms of functional materials, 23 including metal selenides. 24,25 The use of single source precursors in CVD has a number of advantages, not least the simplication of the decomposition mechanism since all required elements are delivered to the desired substrate at the same time. Earlier this year compounds of the type: [Fe(h 5 -…”